Web aligning apparatus



Oct. 16, 1945. MORSE 2,387,036

WEB ALIGNING APPARATUS Filed Dec. 1, 1941 ATTORNEY Patented Oct. 16, 1945 v I UNITED STATES PATENT OFFICE This invention relates to apparatus for guiding or maintaining proper alignment of a web of material such, for example, as the flimsy endless belt of a photograph-print drying machine, as the web is fed longitudinally.

Its chief objects are to provide a highly sensitive and promptly effective apparatus of this kind; to provide simplicity and economy of construction and repair; and to provide a device of this kind adapted to act upon either a vertically or a horizontally-fed reach of the web or upon a portion of the web which is being fed in any other direction. v

Of the accompanying drawing:

Fig. 1 is an elevation of the apparatus in its preferred form, in position for maintaining alignment of a vertically-fed reach of the web, a vertical portion of the web also being shown, and parts being sectioned and broken away.

Fig. 2 is a section on line 2-2 of Fig. 1.

Referring to the drawing, ID, ID are side-frame members, each of which has mounted thereon a bracket II on which is hinged at I2 a clevis-like pair of elbowed links I3, I3. At their spaced apart outer ends the links I3 of each pair straddle and arehinged at I4, It to opposite side members of a web-guiding and roller-journal frame I5, which preferably comprises, as shown, a pair of sheet-metal stampings I5, I5 (see Fig. 2) held apart at their ends by spacer blocks I6, I6 and secured in assembled relation by rivets I1, I! extending through their margins I5, I5 and through the Spacer blocks, each pair of the margins I5P, It thus defining between them a guide slot for the web, 2|, which is to be kept in alignment, as is clearly shown in Fig.- 2.

In each end of the web-guiding and rollerjournal frame I5 is press-fitted a head member I8 provided with journal means I9 for a webaligning, friction surfaced roll 20.

The web, 2I, that is to be maintained in alignment, is threaded through the device as shown clearly in Fig; 2 and is guided to the friction-surfaced roll 20 by one pair of the spaced-apart, guide slot defining margins I5 I5 of the metal stampings I5, on which margins the web slides, and similarly is guided from the roll 20 by the other pair of such margins, the web contacting the roll 20 throughout a large arc, preferably about 180, as shown in Fig. 2.

The construction and arrangement as shown and described is such that if the web gets too far over to the right, for example, as viewed in Fig. 1, assuming that the web is being fed downward through the device, the center of frictional drag of the web upon the margins of the stampings I5 also will move to the right and this will cause the frame I5 and the links I3 to depart from their normal, symmetrical positions and assume g tiisitions such as are shown in dotted lines in Thus the friction-surfaced roll 20 is moved to an angular position such that in passing over it the web is moved back to the middle position and as this takes place the parts of the device move back to their normal, symmetrical, positions, because of the frictional drag of the web upon the device and the caster effect of the obliquely disposed links I3.

By reason of its being free to be rotated by the web the roll 20 has a mode of operation which produces an efiect widely different from what its efiect upon the web would be if the roll were not permitted to rotate. This mode of operation can best be visualized by contemplation of the fact that when the drag of the web has shifted the frame I5 to the dotted-line position of Fig. 1, with the roll 20 disposed obliquely with relation to the path of travel of the web, each point of the web's contact with the roll has, throughout the halfcircle arc of travel of the web in contact with the roll, a component of motion toward the middle line of the web's proper path of travel, so that without slippage of the web on the roll, the web, throughout its width, is set over toward its proper path of travel by the said component of motion.

In the present embodiment the two margins I5, I5", with which the web 2| is shown to be in contact in Fig. 2, constitute frictional means for causing the forward feeding of the web 2I to exert the drag upon the frame I5 which shifts it to positions such as its dotted-line position of Fig. 1 when the web gets out of its proper path of travel.

Similar realigning of the web occurs when it gets too far over to the left.

When the web is fed upward or downward or in an inclined path, with the roller frame I5 lower than the hinge axes I2, gravity slightly resists the movement of the device from its middle, symmetrical position and sustains some of the reaction of the force of the friction roll in the shifting of the web back to middle position, and helps to return the device to middle position, but, when the web is fed in such direction in relation to the device that it reaches the frame I5 after passing the axes I2 the frictional drag of the web upon the device and the caster efiect of the links I3 are suflicient for those purposes, as in the case of the apparatus belLng mounted for acting upon a horizontally-fed reach of the web.

The drag is especially efiective when, as in the drawing, the guide members which maintain the relationship of the web to the realigning roll are non-rotating.

The device provides the advantages set out in the above statement of objects and various modiflcations are possible within the scope of the appended claims.

I claim:

1. Web-aligning apparatus comprising a pair of stationary supports at opposite sides of the webs path of travel, a pair of freely-swinging links pivoted to said supports respectively for swinging in a plane substantiallyparallel to that of the cit-running portion of the web, a frame disposed transversely of the path of the web and pivoted at positions adjacent its respective ends to the swinging ends respectively of said links, a web-guiding roll journaled for rotation on the frame, and a pair of guides on the frame adapted to engage the web substantially throughout its width to compel the web to pass partly around the roll in driving contact therewith substantially throughout the width of the web, the said guides constituting frictional means for causing the pull of the ofi-runnlng portion of the web to exert a forward drag upon the frame.

2. Web-aligning apparatus comprising a pair of stationary supports at opposite sides of the web's path of travel, a pair offreely-swinging links pivoted to said supports respectively for swinging in a plane substantially parallel to that aeezose of the cit-running portion of the web, a frame disposed transversely of the path of the web and pivoted at positions adjacent its respective ends to the swinging ends respectively of said links, a web-guiding roll journaled for rotation on the frame, and a pair of guides on the frame adapted to engage the web substantially throughout its width to compel the web to pass partly around the roll in driving contact therewith substantially throughout the width of the web, the said guides constituting frictional means for causing the pull of the elf-running portion of the web to exert a forward drag upon the frame, and the pivots connecting the links to the supports being farther apart than are those connecting the links to the frame, so that the links are symmetrically oblique to the roll when the frame is in middle position.

3. Web-aligning apparatus comprising a frame pivotaily mounted adjacent the path of movement of the web, for oscillation in a plane substantially parallel to that of the off-running portion of the web, a guide roll journaled for rota- .tion on the frame, anda pair of non-rotating guides on the frame adapted to engage the web substantially throughout its width, to compel the web to pass partly around the roll in driving contact therewith substantially throughout the width of the web, the said non-rotating guides constituting frictional means for causing the oifrunning portion of the web to exert a forward drag upon the frame.

JOHN F. MORSE. 

